A place where you can learn from the rest on O level A-Math, E-Math and Chemistry. Hot tips to score your A1s provided based on years of experience.A Place to relax if you want a laugh.... O Level exams SOS/HELP space :)
O Level Prelims > O Level Exams > Prom > Holidays/Part time work > Christmas! > Release of Results :) Are you ready?

Well Done Lijun. This is a Cedar Girl O level Prelim MCQ and understand that couple of classes were tricked.

For Anonymous, hope you understand what Lijun has done to get the answer. The tricky part is to multiple by 14. Avogadro's number is formally defined as the number of PARTICLES in 1 mole of substance. Do note that PARTICLES can refer to molecules, ions or atoms.

No. of molecules=(25/58)mole x(6x10^23)molecules/mole

No. of atoms=(25/58)(6x10^23)molecules x number of atoms in C4H10(14atoms)=3.621x10^24 atoms